Process for popping corn.



C. K. HARDING.

PROCESS POR POPPING CORN.

APPLICATION FILED NOV Patented July 28, 1914 CHARLES KNOX HARDING, orCHICAGO, ILLINOIS.

'Pnocnss ron roz'erING coRN.

Specification of- Letters Patent.

' Patented July 2s, 1914..

` Application led November 23, 1912. Serial No. 733,213.

n To all whom it may concern f 1 .terior vapor' ressure attainable islimited rapidly as possible to a high temperature,

Be it known that I, CHARLES KNOX HARD- ING, a citizen of the UnitedStates, residing at Chicago, in the county of (Jook and State l ofIllinois, have invented certain new and useful Improvements in Processesfor Popping Corn, of which the following is a specification.

My invention relates generally to improvements in the art of treatingstarchy cereals for food, especially which it is particularly fitted. sl

The object of my invention is to cook, disrupt, enlarge and expand thestarchy interior of-the pop-corn to as great an extent as possible, andto facilitate, regulate, control and insurev uniformity in maintainingimproved conditions in popping corn.

'My invention further comprises new and| useful features of the process,as will be hereinafter shown, described and pointed out in the claim. il

The embodiment of my invention illustrated in the accompanying drawingsshows an apparatus adapted for continuous workingthat is, feeding theunpopped corn in a continuous stream, passing it steadily to a point inthe popping chamber, while it is subject to the action of both the heatand a rapidly flowing current of a gaseous medium, such as air,preferably rareied much below the atmospheric pressure, at the pointwhere the grains explode into many times their original volume; thecurrentof rarefied air immediately carries them out of the poppingchamber and the zone ofhighest temperature, which may be heated moreintensely than in the old intermittent process, where the popped andunpopped corn bothl were exposed for a time together. Y

I have'found that the best results are produced by heating up the grainsof corn as thereby preventing the high pressure vapors from leaking ordiffusing through. the eX- terior hull of the kernel. The maximum inbyattaining t at temperaturel at which the tial destructive distillationbreaks down the mechanical strength of the hull and the kernel explodes,or ops, at Ithis temperature.

As it is desira le to disrupt, distend and pop-corn 4for ,y

expand the starchy interior as much as possible, and it is difficult toincrease the internal vapor pressure beyond 'a certain temperature,according to my invention I reduce the external lgaseous pressure towhich the kernel is exposed at the moment of popping to a pointwhere thevolume assumed by the libera ted vapor becomes many times as large as itwould be if suddenly liberated against the atmospheric pressure. It iswell known that steam at. 1.47 lbs. absolute pressure occupies tenltimes the volume it would at ordinary atmospheric pressure, 14.7pounds.

The drawings showl a central vertical secchamber 2, which may beconstructed of glass. e

Fig. 4 shows a heating chamber for applyingheat to the circulating air,one end of which communicates with the inlet opening* of the blower 3,and the other end is continued to the top of the receiving chamber 2,which forms a part of-a continuous passage through which the current ofair circula'tes. Theheater tube 4 is heated by the gas burner shown at5. The lower portion of the popping chamber 1 is provided wi theelectric heater 6 which is shown as being formed vfrom coils of vhighresistance wires backed by a lining of refractory and insulatingmaterialadapted to radiate heat into the popping chamber and rapidlyimpart a high temperature to the kernels.

In operation, the unpopped corn is fed through the feeding valve 9 andis subjected to the action of the radiant heat from heater 6, at thesame time the fan produces a rapid flow of air which is drawn throughthe heater tube 4 and heated to a relatively high temperature. Thevelocity of the flowing air "tion of an apparatus in which my .process1s suiicient to carry the popped corn out of the `popping chamber andinto the receiver,

where its velocity is materially reduced and the popped corn falls tothe lower portion of the receiver tube, the heated air continuesupwardly and finally passes downward and back through the heater tube 4,and is thus continuously passing through the blower and thus maintainedin circulation and enough heat applied to it to maintain its temperatureso that it will not have a cooling effect. Fig. 1l shows an outlet whichcommunicates through a cooling coil with an air pump for removing alarge part of the air and pressure from the interiorof the apparatus andto remove the excess air which enters by leakage and the operation ofthe feeding valve 9 and also the operation of the discharging valve 7which operates in a well known manner for removing the popped corn fromthe lower part of the receiving chamber 2 while allowin the minimumamount of air to enter. y of the corn which fails to pop is passed onthrough the .CHARLES KNoX HARDING.

Witnesses E. GREATHEAD, W. HARDING.

